Metallic dowel-plate for use in the production of screen-frames, &amp;c.



R. MCKNIGHT. METALLIC DoWBL PLATE FOR USB IN THE PRODUCTION CF SCREEN FRAMES, La.

APPLICATION FILED 00T.9, 191.1.

I 11528,'761. I Patented June4,191.-2.`

UNITED sTATEs PATENT oFnICE.

RICHARDiMCKNIGI-IT, 0F DENVER, COLORADO, ASSIGNORTO THE STEEL TENON MANUFACTURING COMPANY, AcoRroRATIoN oF COLORADO. f

METALLIC DOWEL-PLTE FOR USE IN THE :PRODUCTIONv OF SCREENeFRMES, 86C.

To all whom t may concern.' i

Be it known that I, RICHARD MCKNIGHT, a citizen of the United States'of America, residing in the city yand county of Denver and State of Colorado, have invented anew and useful Metallic Dowel-Plate for Use in the Production of Screen-Frames, &c., of which the following is a specification.

This invention relates to improvements in metallic dowel plates for Connecting the parts of screen and window frames, doors, etc.

The objects of the invention are, to provide a dowel plate for use in theproduction of frames of various kinds, by which the parts of the frame are securely held together without the use of glue or other fastening means. Further, to provide a substantially V-shaped metal dowel platev adapted to be driven into the abutting ends of the frame pieces, so as toconnect them, the plate being formed with right angled blades or tongues which enter the frame pieces and prevent l them from becoming separated, and are sov arranged that when driven into cross-grained wood they enter the wood with a shearing cut. These objects are accomplished by the device illustrated in the accompanying draw ings, in which- Figure l is a front view of a frame, the parts of which are connected by the limproved form of dowel shown in dotted lines, Fig. 2 is a vertical, sectional view thereof, on the line 2 2 of Fig. l, Fig. 3 is an edge view of the frame showing an edge view of the dowel plate and the fingers thereon, which prevent the parts of the frame from becoming separated, Fig. 4 isa front viewfull sizeof the improved' dowel plate, Figs. 5 and 6 are respectively, top edge and side edge views of the same, and Fig. 7 is a front f view of a dowel similar to that shown in the previous views, but provided at one corner with .an apertured extension or ear by which the dowel may also form a hanger when used in connection with the upper corners of screen frames.

Referring to the accompanying drawings,

l indicates a frame, which in the presentinstance, is an ordinary screen frame, and 2 indicates the dowel plates which connect the abutting ends of the frame pieces. These dowels comprise substantially fiat triangular plates of any suitable metal, preferably steel or galvanized iron, two edges of which Specification of Letters Patent.

Patented June 4', 191:2.

Application filed October 9, 1911. Serial No. 653,550;`

are slightly rounded or outwardly curvedL to an apex point, while the remaining, .or top edge, is straight. y,

The apex point', formed by the. convergence of the two curved edges of the dowel, is the entering point, and in practice the ends of the frame strips are slotted toreceive the said dowels; the slot formed by two abutting ends conforms in outline to the curved outline of the-dowel'. The manner of forming these slots is in no way connected with the present invention and further' reference thereto is unnecessary. i

The dowels are formed with laterally projecting fingers 4c which project fromgtheir opposite faces in alternateorderytwo of said fingers being on one side of the vertical' center ofthe plate, while the othery two are positioned on the .other side off the vertical center. The fingers are each formed by cut# ting 'from the plate, in any suitable manner, vertically disposed 'tongueswhich are still united to the plate along one of their` sides, and the metal thus secured is bent out at right angles to the plate along the line of its connection with the plate.

Owing to the fact that the plates are narrowest at their upper corners, the two outer fingers are of less length than the two inner fingers and the inner fingers are approximately the same distance from the center of the plate as the fingers on one side 0f the center of the plate are distant from each other. This arrangement positions the inner fingers a sufficient distance from the abutting ends of the frame pieces to prevent splitting off of the material between the said fingers and the ends of the frame pieces when the dowels are driven in, as will be understood by reference to Fig. 3.

The lower edges of the fingers are cut ofi' to stand at an upward and outward angle from the face of the plate to the outer edge of the plate, and the sides of these edges are beveled, as shown at 5, Fig. 6, and these edges are also sharpened. By forming these edges thus, they will cut their way into the wood, especially against the cross-grain of they wood, as the dowels are driven in with a shearing cut, without tearing the wood or mashing it down beneath the edges, as wouldV be the case if the edges were both straight and blunt.

When these dowels are used in the product-ion of screen frames, those at the two upper corners oi' the frame are preferably formed with extended tongues or ears 6, hav- .Y

ing apertures?, whereby the frame may be supported in a swinging position, and an aperture 8 is formed in the plate, as shown, to receive a retaining screw or nail which is passed through the frame.

In producing the frames. the ends ot' the strips or pieces of which they are formed, are first slotted, as above mentioned, and an end piece and 'two side pieces are placed in the relative posit-ions shown in Fig. l, and securely held together by la suitable clamp, the slots in the'abutting ends registering and `forming a slot having the curved outline of the dowel. The dowel is then driven into t-h'e slot and the fingers 4 enter the wood and securely hold the adjoining pieces from becoming disconnected.

The `curvededges of the dowel may be sharpened, as illustrated, though this feature is immaterial. I

Having described the invention, what I claim as 'new and desire to secure by Letters Patent is:

1 A do'wel, comprising a metal plate having one straight 4edge and two outwardly curved edges which meet at a point, and iingers 'project-ing from `opposite sides of the plate in alternate order, which are formed by cutting vertically disposed tongues from said .plate and bending-the same Vat right angles tothe plate, the lower edges of said lfingers beinginclined and sharpened, said plate being provided with a screw receiving aperture between two of said tongues.

2. A dowel, comprising a substantially triangular shaped metal plate having a straight upper edge and its opposite side curved downwardly from said straight upper edge` and converging equally to an apex point at the center of the width of the plate,

said plate being provided with a plurality of right angled tongue portions stamped out of and turned outwardly from the opposite sides of the plate, said tongues having their lower ends upwardly and outwardly inclined from the face of vthe plate to their outer edges, said inclinedv edge being also beveled along its side to form a wood shearing and cutting edge.

In testimony whereof I ailix my signature in presence of two witnesses.

RICHARD .MCKNIGHT Witnesses GERTRUDE E. DoWN'roN, ELIZABETH V; DUNCAN.

Copies of this patent may b e obtained for iive cents each, by addressing the Commissioner of Patents,

' Washington, D. C. 

